Distribution device

ABSTRACT

A distribution device for distributing electric power comprising a duct including a pair of opposing conductors respectively extending over the length of the duct and connected to an electric source, and a plug detachably mounted to the duct for transmitting the power from the conductors through a pair of contactors of the plug to an associated equipment. Each of the contactors of the plug as inserted between the opposing conductors of the duct is resiliently pressed to each of the conductors in opposite direction to each other when mounted. The plug has a means to resiliently clamp its body to the duct, for allowing the plug to be moved along the duct while keeping the contactors in their resilient contacting position with the conductors.

[ 1 Feb. 1, 1972 [54] DISTRIBUTION DEVICE [72] Inventors: Yoshio Yoshiya; Yoshiyuki Ishida;

Masarnichi Ito, all of Kodoma, Japan Matsushita Denko Kabushiki Kaisha, Osaka, Japan [22] Filed: Nov. 5, 1969 [21] Appl.No.: 874,128

[73] Assignee:

[30] Foreign Application Priority Data Nov. 11, 1968 Japan ..43/98274 Nov. 28, 1968 Japan ..43/103742 Nov. 11, 1968 Japan..... ".44/30957 May 12, 1969 Japan ..44/43314 [52] U.S. Cl. ..339/21 R [51] Int. Cl ..I-I0lr 9/12 [58] Field of Search ..339/14, 20-24, 339/119 [56] References Cited UNITED STATES PATENTS 2,134,753 11/1938 Fisher et al ..339/22 T 2,977,566 3/1961 Neumann et al ..339/119 3,150,908 9/1964 Verrone ..339/9l "W." Mil 3,154,646 10/1964 Jurca et al. ....200/5l 3,422,387 1/1969 Sprigings et al.. ....339/l4 3,503,032 3/1970 Routh et al. ..339/l4 FOREIGN PATENTS OR APPLICATIONS 1,472,664 1/1967 France ..339/l4 Primary Examiner--Marvin A. Champion Assistant Examiner-Robert A. Hafer AttorneyWolfe, Hubbard, Leydig, Voit and Osann, Ltd.

[57] ABSTRACT A distribution device for distributing electric power comprising a duct including a pair of opposing conductors respectively extending over the length of the duct and connected to an electric source, and a plug detachably mounted to the duct for transmitting the power from the conductors through a pair of contactors of the plug to an associated equipment. Each of the contactors of the plug as inserted between the opposing conductors of the duct is resiliently pressed to each of the conductors in opposite direction to each other when mounted. The plug has a means to resiliently clamp its body to the duct, for allowing the plug to be moved along the duct while keeping the contactors in their resilient contacting position with the conductors.

3 Claims, 10 Drawing Figures INVENTORS osmm mm M

ATTORNEYS SHEET 1 BF 3 PMENTED m 1 1972 SHEET 3 BF 3 INVENTOR$ Wsww Ywmm um KM-MM Mmmmwu M0 WWW DISTRIBUTION DEVICE This invention relates to electricity distribution devices and, more particularly, to the distribution device in which distributing plug detachably mounted for connection to channel-shape distribution rail or duct is made to be movable in its mounted state.

In conventional distributing devices, contacting state of pinshaped contactor of the distributing plug with conductors in the distribution rail has been unstable when the plug was moved along the duct as it was mounted to the duct, the conductors have been readily worn out by the contactor and, therefore, it has been difficult to have the plug moved along the duct at its mounted state to the distribution duct. These defects have been inherent to their structure of the conventional devices, since such devices comprise the distribution rail or duct containing a pair of conductors respectively arranged horizontally on each inner surface of opposing slit edges of a slit, and the distributing plug including a contactor portion having pin-shaped contactors at lower surfaces of respective ends of lateral projections formed at upper part of an insulative collector tube having a mounting member provided with a flange part adapted to move in axial directions of the tube, which movement is restricted by an operating screw ring, and the tube is mounted to the duct in such manner that the pin-shaped contactors opposing to the respective conductors of the duct will be brought into horizontal contact with the conductors, respectively, and thereafter the mounting member of the plug will be axially moved toward the duct by rotating the operating screwring so as to press the mounting member to lower surface of the duct and thereby the plug will be fixed to the latter. Thus, in order to move the plug along the duct, the mounting member has first had to be loosened and consequently the horizontal contact of the contactors with the conductors has had to be also loosened.

According to the present invention, a pair of conductor members is arranged vertically in the distribution duct so as to oppose to each other in horizontal direction, the electricity collecting tube of the distributing plug is provided with a pair of contactor members at both side ends of the upper portion of the tube, which members are so arranged as to be provide with a spring action in horizontal direction, and the distributing plug is provided with a mounting member which is given normally an upward axial resiliency, so that, when the plug is mounted to the duct, the contactor members will be resiliently engage the conductor members in vertical relation thereto and the mounting member will also resiliently engage lower surface of the distribution duct so as to hold the plug-in its mounted position. With the above arrangement, the present invention has solved the defects of conventional devices as referred to in the above.

It is an object of the present invention to provide a distribution device in which it is made possible to have the distributing plug freely slided during the same is resiliently mounted to the distribution duct and, thus, while the conducting state is maintained, and to fix the plug at any desired position along the duct.

Other objects and advantages of the invention will become apparent from the following detailed description of preferred embodiments of the present invention taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of the distribution device according to the present invention showing the distributing plug before mounted to the distribution duct.

FIG. 2 is a perspective view of the plug as disassembled.

FIGS. 3 and 4 show states in which the plug is mounted to the duct and, specifically, FIG. 3 is a vertical view of the state before the plug is fastened and FIG. 4 is the state where the plug is fastened.

FIGS. 5 through 8 show another embodiment of the plug and, specifically, FIG. 5 is a vertically sectioned view thereof, FIG. 6 is a perspective view of head part thereof as disassembled, and FIGS. 7 and 8 are plan views showing noncontacting and contacting states of .the contactors and conductor members, respectively.

.FIGS.- 9 and 10 show a further embodiment of the plug and, specifically, FIG. 9 is a partly sectioned vertical view of the plug as mounted to the distribution duct and FIG. 10 is a perspective view of head part of the plug as disassembled.

While the present invention shall be explained with reference to certain preferable embodiments as illustrated, it will be-understood that the invention should not be limited to the particular embodiments but rather include all modifications, alterations and equivalent arrangements to be included in the scope of the appended claims.

Turning to the drawings, FIGS. 1 through 4 show a first embodiment of the present invention. In the drawings, P is a distributing plug. As will be best seen in FIG. 2, the plug P comprises substantially four parts, first of which is an electricity collecting tube 1 made of a molded synthetic resin tube of a plastic or the like and provided at its upper part with projections 2formed symmetrically at both sides of a protuberant part 3. T he tube has a boss 4 projected below the part 3, a thread 5 around lower part periphery and a through hole 6 at the center for passing electric source wires therethrough. 7 is a contacting member made of such electroconductive material as phosphor bronze plate or the like as bent in a U-shape so as to have an arcuate portion a and to be provided with inwardly compressing resiliency. The contacting member 7 will be mounted at each of the projections 2 so as to cover its forward end with the arcuate portion a. An end of the member 7 will be fixed to a sidewall of the projection 2 so that the other end will be freely slidable along the opposite sidewall of the same projection 2 and thus the arcuate portion 2 will provide a spring action in horizontal lateral direction. The contactor members 7 are respectively connected to an end of each of electric source wires 8 passed through the hole 6. Second one of the said four parts if a mounting member 14 including a flange part 12 and a cylindrical part 13. The flange part 12 is provided at its upper surface end edges along the center line with engaging parts 9 for engaging in the slit of distributing duct and with an engaging hole 11 at the center having a groove 10 for receiving the boss 4 of the tube 1. The cylindri' cal par t' l3 is integrally formed under the engaging hole II with the flange part 12, and is adapted to receive therein a pushup spring 15 so as to have the mounting member 14 normally resiliently biased in upward direction when the member 14 and spring 15 are mounted around the tube 1. Third one of the fourparts is an operating member 19 having at upper and lower ends cylindrical locking projections 16 and I7, respectively, and around inner peripheral surface a thread l8, with which the operating member 19 will be engaged with the threaded part 5 of the tube 1. The pushup spring 15 will be pushed upwardly at its lower end by upper end surface of the upper locking projection 16 so that the mounting member 14 will be resiliently urged in upward direction. The last one of the aforementioned four parts of the plug P is a fixing member 22 having a lock cylinder 20 for locking the lower projection 17 of operating member 19 mounted around lower tube part of the tube 1 as engaged with the threaded part 5, and a thread 21 around inner periphery thereof. At its lower part, the fixing member 22 is provided with a screw hole 23, into which a screw 24 will be screwed so as to fix the member 22 to the tube 1.

Referring now to FIG. 1, H is a distributing duct, which is shownhere fragmentarily with an end vertically sectioned. The duct-H comprises generally an insulator member 28 of a reverse U-shape opened at lower surface as a long continuous opening 25 and containing a pair of conductor members 27, and a channel-shaped housing 33 receiving therein the insulator 28 and likely opened at its lower surface as a long continuous slit 31 restricted at both sides by edges 32. The conductors 27 made, for example, from a copper strip, respectively, are arranged inside both sidewalls 26 of the insulator 28 so as to oppose in vertical relation to each other through a distance adapted-to be resiliently engaged by each of the contactors 7 of the disiributing plug P, and are rigidly held by the insulator 28 at their upper andlower ends as immersed into the insulator body. The insulator 28 is in turn fixedly held in the housing 33 as locked by locking projections 29 and 30 respectively provided on upper and lower inner surfaces of the housing 33 at each corner of the insulator 28, in such manner that the opening 25 ofthe insulator 28 and the slit 31 of the housing 33 are aligned with each other.

In mounting the distributing plug P to the duct H, the protuberant part 3 of the plug is first inserted into the slit 31 in such way that the engaging parts 9 on the flange 12 will be right angle with respect to longitudinal direction of the slit 31. Then, at a position where the flange 12 is butted against the edges 32 of housing 33 and the protuberance 3 is, on the other hand, passed into the housing beyond the edges 32 against upward resiliency of the mounting member 14, the plug P is turned around by 90 so that the protuberant part 3 will be also turned by 90 inside the housing. At the turned around position, the projections 2 of protuberant part 3 will be bridged across the housing edges 32 and, at the same time, the contacting members 7 at forward ends of the projections 2 are resiliently brought into contact with the conductors 27 of the duct H in the vertical relation to each other, respectively. At the same time, the engaging parts 9 of the flange 12 will engage into the slit 31, thereby the plug P is prevented from being axially rotated. In this position, the mounting member 14 will be resiliently pressed at its upper surface of the flange 12 against lower surface of the housing 33 automatically by means of upward resiliency of the pushup spring 15 so that the slit edges 32 will be resiliently held between the projections 2 ofthe protuberant portion 3 and the flange 12 of the mounting member 14, as shown in FIG. 3. A

Under the above mentioned condition, an electric source current will be supplied from the duct H to the electric source wires 8 passed through the electricity collecting tube 1 of the distributing plug P, through the contacting areas between the conductors 27 and the contactors 7 established by means of the spring action of the latter, so that such a load (not shown) as a lighting equipment or the like mounted to lower end of the plug and connected to the other end of the wires 8 will receive the power.

In such conducting state as above, since the plug P is resiliently mounted to the duct H with its mounting member 14 butted against lower surface of the duct only by the upward spring action of the pushup spring 15, the plug P can be freely slided along the slit 31 against the resiliency of the spring 15 to any desired position on the duct H. In order to fix the plug at the desired position, the operating member 19 may be simply turned so as to be moved along the tube 1 upwardly, until the mounting member 14 will be rigidly pressed to the lower surface of the duct H.

Turning next to FIGS. 5 through 8, there is shown another embodiment of the present invention. That is, the contacting members 7 of the distributing plug P may be made in such structure that each contacting piece 34 bent in a U-shape so as to be provided with an arcuate part a will have a longer extended leg than a free end 35 at the side for fixing the contacting member, and the extended leg will be provided with an integral base piece 36 further extending downwardly at a right angle with respect to the extended leg and connected to an end of the source wires 8. In the present instance, the protuberant part 3 is formed to have a groove 37 of substantially a reverse Z-shape connected with the central through hole 6 for passing the electric source wires and directly with the downward extending collecting tube 1, and small grooves 38. Each of the free ends 35 of the contacting members will be fitted in the small grooves 38, respectively, and the other extended legs are fitted into extended parts of the reverse Z- shaped groove 38, respectively, with the base pieces 36 and the wires 8 connected thereto inserted into the through hole 6, so that the arcuate portions a are extended out of forward end peripheries of the protuberance 3, respectively. A separator 41 of a molded synthetic resin or the like having a wedge member 39 and a cap integrally formed above the member 39 will be fitted on the protuberance 3 in such manner that the wedge member 39 will be inserted into the hole 6 and between the respective base pieces 36 so as to urge the pieces against opposed inner periphery of the hole 6 and to, thus, fix the contacting members 7 in the hole as separated from each other and, at the same time, the cap 40 will cover and insulate the upper surface, as shown in H6. 5, except the arcuate parts a of the contacting members 7. With this arrangement, a distributing plug P having the contacting members adapted to perform the spring action in horizontal direction at their arcuate portions exposed out of the lateral forward ends of the protuberant part 3 with an end remained in free state will be formed.

As shown in FIG. 7, the contacting members 7 will remain in free extended state, before they are brought into contact with the conductors 27 of the duct H. When the plug P is mounted to the duct and rotated so that the members 7 engage the conductors 27, the arcuate portions a of the members 7 will be depressed by the conductors and the free ends 35 of the members 7 will be moved along the small groove 38 against their own resiliency. Thus, the arcuate portions 0 of the contact members 7 will be deformed as shown in FIG. 8 and will closely engage the conductors in vertical relation thereto with the horizontally directioned spring action of the members 7 now being actuated. Thus, it is made possible to have the plug slided along the duct while keeping the conducting state between the contacting members and the conductors.

In a further embodiment of the present invention, shown in FIGS. 9 and 10, the plug P is formed in a modified structure specifically with respect to the contacting members and, optionally, the mounting means. As will be seen best in FIG. 10, the upper end protuberant part 3 of the collecting tube 1 made likely ofa molded synthetic resin or the like is formed to have a longitudinal recess 42 connected to the through hole 6 at the center and opened at both forward ends. Each of the contacting members 7 is formed from a continuous plate material to have a spherical free end 44, an inclined leg 46 subsequent to bent part 45 of laterally extending part 48, and base portion 47 below the leg 46. The base portion 47 will be connected to an end of the wires 8. Two of the contacting members 7 thus formed will be fitted in the recess 42 and the hole 6 so as to longitudinally symmetrically oppose to each other, with the lateral extensions 48 laid in the recess 42 so as to have the spherical ends 44 extended out of the forward ends of the protuberant part 3, and with the legs 46 and base portions 47, as well as the wires 8 connected to the latter, inserted in the hole 6. A separator 52 likely of a synthetic resin or the like having a wedge portion 50 with inclined surfaces 49 at its upper both sides and a cap 51 will be fitted on the top of the protuberant part 3 so as to insert its wedge portion 50 into the hole 6. The wedge portion 50 will urge each of the base portions 47 of the contacting members 7 against each of opposing inner peripheral walls of the through hole 6 so as to fix them in the position, and the cap 51 will cover and insulate the lateral extensions 48 of the members 7 laid in the recess 42 at the top of protuberant part 3, while the spherical free ends 44 are respectively urged to extend out of each of the opened forward ends of the recess 42 in the horizontal direction.

With the above arrangement of the third embodiment, the plug P will be also provided with the contacting members 7 having the spring action at the spherical free ends in the horizontal direction, at which ends the members 7 are to be resiliently engaged by the distributing conductors.

In the present embodiment, further, the mounting mechanism of the plug to the distribution duct has the following structure.

While the pushup spring 15 is similarly set around upper part of the collecting tube 1 and covered by the mounting member 14, lower end of the spring 15 is made to be supported, in the present instance, by upper end of upwardly extended cylinder part of the fixing member 22. Around outer periphery of said extended cylinder part is formed a screw thread 43, to which the operating member 19 having also a screw thread around its inner wall (but without the upper and lower locking projections 16 and 17 in this case) is fitted, so

that the member 19 will be movable upward and downward when rotated along the threaded upward extension of the fixing member 22. The member 22 is fixed at a proper position around the lower portion of the collecting tube 1 (in this case the tube 1 has no threaded part) by means of the screw 24 so as to leave a sufficient space between lower end of the mounting member 14 and upper end of raised portion of the fixing member 22 for the movement of the operating member 19. Thus, while the mounting member 14 is movable downwardly against the upward biasing force of spring upon receiving any downward force when the member 19 is kept at its lower position, the member 14 will be locked at its upwardly biased position by the operating member 19 when the latter is positioned at the uppermost position where the same engages the lower end of the member 14.

Leaving the operating member 19 at its lower position, when the protuberant part 3 of the plug P will now be inserted into the duct H from the slit 31 at lower surface of the duct and rotated therein, then the spherical free ends 44 of the contacting members 7 initiate to contact with the conductor members 27 in the duct H with their own resiliency in horizontal direction increased as rotated. AT the position where the plug P is rotated by 90, the lateral extensions 48 of the contactors 7 are retracted into their innermost position with the inclined legs 46 urged into spaces formed by inclined surfaces 49 of the separator 52, so that the contacting pressure of the contactors 7 against the conductors 27 will be most increased and, at the same time, the spherical ends 44 will closely engage the conductors in the vertical relation thereto. Thus, it is possible to slidingly move the plug P along the duct l-l while the conducting state between the plug and the duct is kept with the strongest contacting pressure.

According to the present invention, therefore, the distributing plug is so formed as to be provided with the contacting members which has a horizontally directed spring action at both ends of the protuberant part formed at the top of power collecting tube, the mounting member fitted movably on the tube beneath the protuberant part thereof is arranged so as to be always spring biased in the upward direction toward the side of the duct, and the duct is provided with the conductor members as opposed to each other in vertical relation to the slit at the lower side of the duct. With these features of the structure, the plug is capable of'being stably mounted to the duct as resiliently held thereto in an automatic manner by means of the upward spring biasing force always presented to the mounting member of the plug when the contacting portion at the top of the plug is inserted, while being kept in aligned angle with the slit of the duct, into the duct and rotated by 90. At the same time, the contacting members of the plug are brought into firm contact with the respective conductor members of the duct in the vertical relation thereto with the horizontally directional spring biasing force automatically increased as the plug is rotated, so that the increased contacting pressure between the conductor and contactor members will be always kept at a sufficient amount for the conduction. With the above advantages established according to the present invention, the distributing plug is featured in that its position on the duct can be freely changed as desired by freely moving the plug along the duct while desired conducting state of electricity from the duct to the plug is sufficiently maintained.

While the present invention has been described specifically with reference to the illustrated embodiment, the invention is not to be intentionally limited to the specific structures as shown and disclosed, For example, the conductor members may be made in the form of wire, in the case where the contacting members take the form as shown in FIG. 10.

What is claimed is:

l. A distribution device comprising a combination of a duct containing conductor members connected to an electric source and a plug connected to an electric equipment or apparatus and mounted detachably to said duct; said duct comprising a pair of conductor members arranged to oppose each other as spaced by a proper distance, and insulating member holding therein said conductor members in said arrangement and having a longitudinal opening between said pair of opposing conductor members, and a channel-shape housing containing said insulating member and having a longitudinal slit in alignment with said opening of the insulating member; and said plug comprising a top member of an insulative material to be bridged between said pair of opposing conductor members of the duct within said longitudinal slit of said housing when the plug is mounted to the duct, a pair of contacting members of a resilient plate material secured to opposite sides of said top member for making electrical contact with said conductor membersof the duct, said resilient contacting members being formed in'a U-shape and fitted respectively at each forward end of laterally extending arms provided integrally at the top portion of an insulative material of the plug with an end fixed to the arm and connected to electric wire and'with the other end kept free, so that each arcuate end of the contacting members will resiliently engage one of the conductor members,

said resilient contacting members being secured to said top member so that the resiliency thereof biases said contacting members away from each other and into engagement with said conductor members along an a six transverse to the axis of said conductor members and the longitudinal axis of said plug said contacting members being electrically connected to electrical leads for connecting said plug to said electrical equipment, a mounting means provided on the plug body for longitudinal sliding movement and normally biased longitudinally toward the top portion of the plug for resiliently clamping peripheral edges of said slit of the duct between the mounting means and said top portion of the plug so that the plug will be movable along the slit of the duct while the resilient contact of the contacting members with the conductor members is maintained, said mounting means also including a pair of latching elements adapted to fit within said longitudinal slit for blocking rotational and traverse movement of said mounting means relative to said housing and said conductor members while permitting longitudinal movement of said mounting means relative to said conductor members.

2. A distribution device as set forth in claim 1 wherein said plug comprises a mounting member movably fitted on the plug body and normally biased toward the lower end of said top portion by means of a spring contained in the plug body, and an operating member movably fitted on the plug body so to be capable of locking said mounting member at its biased posi tion clamping peripheral edges of the slit of the duct between the mounting member and the top portion of the plug when the operating member is retained in its position butted to the other end-of the mounting member, said capable of allowing the mounting member to be resiliently movable when the operatingmember is mounted at its position spaced from the mounting member.

3. A distribution device comprising a combination of a duct containing conductor members connected to an electric source and a plug connected to an electric equipment or apparatus and mounted detachably to said duct; said duct comprising a'pair of conductor members arranged to oppose each other as spaced by a proper distance, an insulating member holding therein said conductor members in said arrangement and having a longitudinal opening between said pair of opposing conductor members, and a channel-shaped housing containing said insulating member and having a longitudinal slit in alignmentwith said opening of said insulating member; and said plug comprising a top member of an insulative material to be bridged between said pair of opposing conductor members of the duct within said longitudinal slit of said housing when the plug is mounted to the duct, a pair of said top member for making electrical contact with said conductor members of the duct, said resilient contacting members being formed in a U- shape and fitted respectively at each forward end of laterally extendingarms provided integrally at the top portion of an insulative material of the plug with an end extending into axial hole of the plug for passing therethrough associated electric wires with the members and with the other end kept free around said arm so that each arcuate end of the contacting members will resiliently engage one of the conductor members, and said extended ends of the contacting members are fixed in said hole as separated by an insulative separator inserted between the extended ends in the hole, said resilient contacting members being secured to said top member so that the resiliency thereof biases said contacting member away from each other and into engagement with said conductor members along an axis transverse to the axis of said conductor members and the longitudinal axis of said plug, said contacting members being electrically connected to said electrical wires for connecting said plug to said electric equipment, a mounting means provided on the plug body for longitudinal sliding movement and normally biased longitudinally toward the top portion of the plug for resiliently clamping peripheral edges of said slit of the duct between the mounting means and said top portion of the plug so that the plug will be movable along the slit of the duct while the resilient contact of the contacting members with the conductor members is maintained, said mounting means also including a pair of latching elements adapted to fit within said longitudinal slit for blocking rotational and transverse movement of said mounting means relative to said housing and said conductor members while permitting longitudinal movement of said mounting means relative to said conductor members. 

1. A distribution device comprising a combination of a duct containing conductor members connected to an electric source and a plug connected to an electric equipment or apparatus and mounted detachably to said duct; said duct comprising a pair of conductor members arranged to oppose each other as spaced by a proper distance, and insulating member holding therein said conductor members in said arrangement and having a longitudinal opening between said pair of opposing conductor members, and a channel-shape housing containing said insulating member and having a longitudinal slit in alignment with said opening of the insulating member; and said plug comprising a top member of an insulative material to be bridged between said pair of opposing conductor members of the duct within said longitudinal slit of said housing when the plug is mounted to the duct, a pair of contacting members of a resilient plate material secured to opposite sides of said top member for making electrical contact with said conductor members of the duct, said resilient contacting members being formed in A U-shape and fitted respectively at each forward end of laterally extending arms provided integrally at the top portion of an insulative material of the plug with an end fixed to the arm and connected to electric wire and with the other end kept free, so that each arcuate end of the contacting members will resiliently engage one of the conductor members, said resilient contacting members being secured to said top member so that the resiliency thereof biases said contacting members away from each other and into engagement with said conductor members along an a six transverse to the axis of said conductor members and the longitudinal axis of said plug said contacting members being electrically connected to electrical leads for connecting said plug to said electrical equipment, a mounting means provided on the plug body for longitudinal sliding movement and normally biased longitudinally toward the top portion of the plug for resiliently clamping peripheral edges of said slit of the duct between the mounting means and said top portion of the plug so that the plug will be movable along the slit of the duct while the resilient contact of the contacting members with the conductor members is maintained, said mounting means also including a pair of latching elements adapted to fit within said longitudinal slit for blocking rotational and traverse movement of said mounting means relative to said housing and said conductor members while permitting longitudinal movement of said mounting means relative to said conductor members.
 2. A distribution device as set forth in claim 1 wherein said plug comprises a mounting member movably fitted on the plug body and normally biased toward the lower end of said top portion by means of a spring contained in the plug body, and an operating member movably fitted on the plug body so to be capable of locking said mounting member at its biased position clamping peripheral edges of the slit of the duct between the mounting member and the top portion of the plug when the operating member is retained in its position butted to the other end of the mounting member, said capable of allowing the mounting member to be resiliently movable when the operating member is mounted at its position spaced from the mounting member.
 3. A distribution device comprising a combination of a duct containing conductor members connected to an electric source and a plug connected to an electric equipment or apparatus and mounted detachably to said duct; said duct comprising a pair of conductor members arranged to oppose each other as spaced by a proper distance, an insulating member holding therein said conductor members in said arrangement and having a longitudinal opening between said pair of opposing conductor members, and a channel-shaped housing containing said insulating member and having a longitudinal slit in alignment with said opening of said insulating member; and said plug comprising a top member of an insulative material to be bridged between said pair of opposing conductor members of the duct within said longitudinal slit of said housing when the plug is mounted to the duct, a pair of said top member for making electrical contact with said conductor members of the duct, said resilient contacting members being formed in a U-shape and fitted respectively at each forward end of laterally extending arms provided integrally at the top portion of an insulative material of the plug with an end extending into axial hole of the plug for passing therethrough associated electric wires with the members and with the other end kept free around said arm so that each arcuate end of the contacting members will resiliently engage one of the conductor members, and said extended ends of the contacting members are fixed in said hole as separated by an insulative separator inserted between the extended ends in the hole, said resilient contacting members being secured to said top member so that the resiliency thereof biases said contacting member away from each other and into Engagement with said conductor members along an axis transverse to the axis of said conductor members and the longitudinal axis of said plug, said contacting members being electrically connected to said electrical wires for connecting said plug to said electric equipment, a mounting means provided on the plug body for longitudinal sliding movement and normally biased longitudinally toward the top portion of the plug for resiliently clamping peripheral edges of said slit of the duct between the mounting means and said top portion of the plug so that the plug will be movable along the slit of the duct while the resilient contact of the contacting members with the conductor members is maintained, said mounting means also including a pair of latching elements adapted to fit within said longitudinal slit for blocking rotational and transverse movement of said mounting means relative to said housing and said conductor members while permitting longitudinal movement of said mounting means relative to said conductor members. 